These zones to be treated consist of several plate metal panels. Renovating the panels avoids the need for total dismantling of the various parts of the clean room, followed by its reassembly. The handling time is long since these panels are fixed to rails which are themselves fixed to the walls and often nested into the ceiling and the floor resin of the building. Repair without dismantling appears to be a simpler solution since it avoids the need for suspending, for a certain time, the activity of the clean rooms.
Hydrogen peroxide is used for disinfecting clean rooms. Hydrogen peroxide is the replacement for formaldehyde, the use of which was stopped by decree following the order of Jan. 5, 1993. Hydrogen peroxide, also known as aqueous hydrogen peroxide solution, allows sterilization, i.e. the total destruction of all microorganisms, including bacterial spores, and disinfection, i.e. the destruction and removal of specific types of microorganisms.
Hydrogen peroxide is used in gaseous form. For example, liquid 30% hydrogen peroxide is vaporized to obtain about 1200 ppm. The vapor splits into water and non-toxic oxygen and affords a sterilizing action for decontaminating the equipment and materials of confinement laboratories.
The partition walls of clean rooms must meet performance standards imposed by the constraints for controlling this contamination. This is why the surface state of the panels must be maintained over time. However, it arises that activity-related incidents compromise these performance standards due to scratching or chemical impairment of the surface. For example, during the decontamination phase, scratches cause the paint of the panels to blister, and, over time, it will flake off.
Document FR 2 915 690 describes a process for painting a non-metallic support, comprising steps of sanding to make the support smooth, the application of several coats of motor vehicle primer diluted to about 50%, sanding before each coat, the application of motor vehicle bodywork caulking compound to even out defects in the support, the application of a coat of varnish and buffing. By means of this process, a smooth, water-repellent, glossy and resistant surface state is found. However, this process cannot be adapted to the sheet metal of the panels of a clean room since they are metallic. Furthermore, this process is not suited to withstanding decontamination with hydrogen peroxide.
The aim of the present invention is to overcome these drawbacks and to propose a process for repairing and renovating panels forming a clean room, while at the same time withstanding decontamination with hydrogen peroxide.